Figure 1.

Histone deacetylase inhibitors block cartilage glycosaminoglycan and collagen loss
induced by IL-1α/OSM. Bovine nasal cartilage discs were cultured in the presence or
absence of I/O (a combination of IL-1α and oncostatin M (OSM)) and a histone deacetylase
inhibitor, either (a) I/O (1 ng/ml IL-1α, 10 ng/ml OSM) with trichostatin A (TSA) or (b) I/O (0.2 ng/ml IL-1α, 2 ng/ml OSM) with sodium butyrate (NaBy). Cartilage was incubated
until day 7 and supernates were harvested and replaced with fresh reagents until day
14. Glycosaminoglycan (GAG) release is shown as at day 7 and was assayed using the
dimethylmethylene blue method. Collagen release is shown as at day 14 and was measured
using an assay for hydroxyproline. Viability was assessed by measuring lactate dehydrogenase
in the conditioned medium. Assays were performed at least twice using quadruplicate
samples; means ± standard deviations are represented. *P < 0.05, **P < 0.01, ***P < 0.001.